Brake systems that can be actuated by a pressure medium, e.g., disk brake systems for rail and commercial vehicles, exhibit in their design as caliper constructions a piston that is guided pressure-tight in a housing or in the caliper construction and can be actuated by an hydraulic medium and that, when actuated, act relative to a brake shoe bearing a brake lining, in order to force said brake shoe with its brake lining against a brake disk to be braked. Hydraulic cylinders operating in this manner can also be used in so-called caliper constructions, preferably for rail vehicles, in order to force the arms of a caliper on both sides against a brake disk to be braked.
Actively acting clamping pistons of such brake actuating elements can be subjected in the inactive state, i.e., in the position of rest, to axially directed impact forces, which can lead to the clamping pistons beings pushed back into the housing. accommodating them. This unintentional pushing back is a drawback, since it results in an increase in the leading stroke, in the final analysis a longer braking distance.
To overcome this problem, it is possible to guide the clamping piston by means of a clamping spring frictional force relative to the housing accommodating said clamping piston. However, this solution has the drawback that the clamping spring frictional force has a negative effect on the hysteresis. For floating caliper designs with great mass and relatively high lateral movements of the brake disk, this frictional force would have to be unacceptably high.